Radio frequency transmissions of voice and data are used in many commercial, industrial and military situations. In some applications of RF technology, the size and power requirements of the transmission and reception equipment are not a crucial factor. For example, a radio station in a major metropolitan area can well afford very large transmitting towers from which highly amplified signals are radiated over substantial distances. In other applications however, for example when the transmitter and/or receiver are hand-held devices using commercial off the shelf (COTS) components, the size and power requirements of the equipment become much more critical. That is, as the equipment becomes smaller, the available space for power supplies, usually a battery, becomes commensurately smaller. With the smaller power supply, the range for a RF transmitter decreases, and/or the lifespan of the power supply decreases.
In applications where the power supply is somewhat limited, power can be conserved by narrowing the receiver bandwidth, thus decreasing the transmission data rate. Alternatively, the power in such situations can be kept at the same level, and the data can be transmitted over a greater range through narrower bandwidth transmission and consequent decrease in the data rate. However, by narrowing the bandwidth, any drift or fluctuation in the transmitting frequency or receiver electronics, especially at higher transmission frequencies, will result in lost data and other errors. There is therefore lacking in the art a reliable RF system that can increase the range of transmission by narrowing the bandwidth, thus decreasing the data transmission rate.